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1.
Nanomicro Lett ; 16(1): 154, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499708

RESUMO

The battery technology progress has been a contradictory process in which performance improvement and hidden risks coexist. Now the battery is still a "black box", thus requiring a deep understanding of its internal state. The battery should "sense its internal physical/chemical conditions", which puts strict requirements on embedded sensing parts. This paper summarizes the application of advanced optical fiber sensors in lithium-ion batteries and energy storage technologies that may be mass deployed, focuses on the insights of advanced optical fiber sensors into the processes of one-dimensional nano-micro-level battery material structural phase transition, electrolyte degradation, electrode-electrolyte interface dynamics to three-dimensional macro-safety evolution. The paper contributes to understanding how to use optical fiber sensors to achieve "real" and "embedded" monitoring. Through the inherent advantages of the advanced optical fiber sensor, it helps clarify the battery internal state and reaction mechanism, aiding in the establishment of more detailed models. These advancements can promote the development of smart batteries, with significant importance lying in essentially promoting the improvement of system consistency. Furthermore, with the help of smart batteries in the future, the importance of consistency can be weakened or even eliminated. The application of advanced optical fiber sensors helps comprehensively improve the battery quality, reliability, and life.

2.
Sci Bull (Beijing) ; 69(6): 747-755, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38331706

RESUMO

The realization of spin-orbit-coupled ultracold gases has driven a wide range of research and is typically based on the rotating wave approximation (RWA). By neglecting the counter-rotating terms, RWA characterizes a single near-resonant spin-orbit (SO) coupling in a two-level system. Here, we propose and experimentally realize a new scheme for achieving a pair of two-dimensional (2D) SO couplings for ultracold fermions beyond RWA. This work not only realizes the first anomalous Floquet topological Fermi gas beyond RWA, but also significantly improves the lifetime of the 2D-SO-coupled Fermi gas. Based on pump-probe quench measurements, we observe a deterministic phase relation between two sets of SO couplings, which is characteristic of our beyond-RWA scheme and enables the two SO couplings to be simultaneously tuned to the optimum 2D configurations. We observe intriguing band topology by measuring two-ring band-inversion surfaces, quantitatively consistent with a Floquet topological Fermi gas in the regime of high Chern numbers. Our study can open an avenue to explore exotic SO physics and anomalous topological states based on long-lived SO-coupled ultracold fermions.

3.
Environ Sci Pollut Res Int ; 30(58): 122774-122790, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37978124

RESUMO

Facing the problem of a lack of endogenous incentive mechanisms for the development of green finance, we regard blockchain technology as an institutional technology and elevate it to the height of governance mechanisms. Using a dynamic stochastic general equilibrium (DSGE) model framework, we compare and analyze its effects with traditional supportive policies such as fiscal subsidies. The modeling simulation results show that the blockchain green finance platform model is conducive to better promoting the development of green finance. Subsequently, we construct a financial technology development index centered on blockchain technology and empirically test the impact of blockchain financial technology on the level of green finance development from both the supply and demand sides. The results show that the development of blockchain financial technology has significantly increased the scale of green credit issuance and effectively eased the financing constraints of green enterprises, reducing financing costs. We conduct an economic analysis of the impact of blockchain financial technology on the development of green finance, providing a feasible path for the integration and development of green finance and financial technology.


Assuntos
Blockchain , Simulação por Computador , Cabeça , Instalações de Saúde , Tecnologia , China , Desenvolvimento Econômico
4.
Chem Commun (Camb) ; 59(6): 712-715, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36541014

RESUMO

To achieve stable Li anode cycling with a high-voltage cathode and high efficiency, a novel ester diluent-based localized high-concentration electrolyte (LHCE) was successfully applied. The oxidation resistance of the high-concentration electrolyte is retained after dilution. More than 99.5% Coulombic efficiency is achieved in Li||Cu cells owing to the optimized physical properties, and the robust SEI film enables superior long-term operation with a high-voltage cathode. This strategy verifies the effectiveness of developing ester diluents for LHCEs applied in lithium metal batteries.

5.
Int J Clin Pharm ; 44(6): 1232-1246, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35951217

RESUMO

BACKGROUND: Multitargeted tyrosine kinase inhibitors (TKIs) are used to treat advanced non-small cell lung cancer (NSCLC). Their efficacy and safety have been studied in randomized controlled trials. AIM: This meta-analysis aimed to summarize the most up-to-date evidence regarding the efficacy and adverse events of TKIs in NSCLC treatment. METHOD: Randomized controlled trials were searched from PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials. The intervention arm was the TKI-containing group, and the control arm was the TKI-free group. Objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival, and adverse events were extracted and synthesized. The last search was performed in April 2022. Two researchers independently screened articles, extracted data, and evaluated the quality of the included studies. The Cochrane risk-of-bias tool was used to assess the quality of each study. Random or fixed-effect models were used in statistical methods. I2 statistics were used to assess heterogeneity. RESULTS: Thirty-one studies (12,517 patients) were included. Compared to the control group, the TKI group had significantly higher ORR (relative risk RR 1.52, 95% confidence interval, CI [1.29, 1.80], P < 0.05), DCR (RR 1.34, 95%CI [1.19, 1.51], P < 0.05), and prolonged PFS (hazard ratio HR 0.67, 95%CI [0.59, 0.77], P < 0.05). The TKI group showed a higher rate of adverse events (RR 1.70, 95%CI [1.34, 2.16], P < 0.05) and grade 3-5 adverse events (RR 1.59, 95% CI [1.35, 1.88], P < 0.05). CONCLUSION: TKIs could increase ORR and DCR and prolong PFS for advanced NSCLC. Adverse events should be closely monitored.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Proteínas Quinases/efeitos adversos , Antineoplásicos/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Cell Transplant ; 31: 9636897221108890, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35801674

RESUMO

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is one of the consolidation modalities for adult patients with T-cell lymphoblastic lymphoma (T-LBL). However, the optimal conditioning regimen needs to be explored. In the present study, 40 patients with T-LBL undergoing allo-HSCT were retrospectively analyzed, including 23/40 (57.5%) with total body irradiation (TBI)-based conditioning regimen and 17/40 (42.5%) with busulfan (BU)-based regimen. TBI-based regimen significantly increased the cumulative incidence (CI) of grade II to IV acute graft-versus-host disease (aGvHD) as compared with BU-based regimen (13.0% vs 0%, P = 0.000). The relapse risk was significantly lowered in TBI-based group with a 2-year CI of relapse (CIR) of 9.1% as compared with that of 49.6% in BU-based group (P = 0.008). The 1-year and 2-year non-relapse mortalities (NRMs) for all patients were 5.0% and 10.3%, respectively. The 1-year and 2-year NRMs were 8.9% and 16.0% in TBI-based group, and 0.00% and 0.00% in BU-based group (P = 0.140). The 2-year probabilities of overall survival (OS) and relapse-free survival (RFS) were 83.0% [95% confidence interval, 63.4%-100%] and 74.0% (95% confidence interval, 54.4%-93.6%) in TBI-based group, which were higher than that of 35.0% (95% confidence interval, 0.0%-72.2%) and 50.0% (95% confidence interval, 24.5%-75.4%) in BU-based group, respectively (P = 0.020 for OS and P = 0.081 for RFS). In multivariate analysis, TBI-based regimen significantly reduced the risk of relapse [subdistribution hazard ratio (SHR) = 0.030, 95% CI, 0.002-0.040, P = 0.000] and improved the OS [hazard ratio (HR) 0.121, 95% CI, 0.021-0.683, P = 0.017] as an independent prognostic factor. These results suggested that TBI-based regimen might be an optimal choice for adult patients with T-LBL undergoing allo-HSCT.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Transplante de Células-Tronco de Sangue Periférico , Leucemia-Linfoma Linfoblástico de Células Precursoras , Adulto , Bussulfano/uso terapêutico , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Transplante de Células-Tronco de Sangue Periférico/efeitos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Recidiva , Estudos Retrospectivos , Linfócitos T , Condicionamento Pré-Transplante/métodos , Irradiação Corporal Total/efeitos adversos
7.
Front Plant Sci ; 13: 836519, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35222493

RESUMO

Light-triggered transcriptome reprogramming is critical for promoting photomorphogenesis in Arabidopsis seedlings. Nonetheless, recent studies have shed light on the importance of alternative pre-mRNA splicing (AS) in photomorphogenesis. The splicing factors splicing factor for phytochrome signaling (SFPS) and reduced red-light responses in cry1cry2 background1 (RRC1) are involved in the phytochrome B (phyB) signaling pathway and promote photomorphogenesis by controlling pre-mRNA splicing of light- and clock-related genes. However, splicing factors that serve as repressors in phyB signaling pathway remain unreported. Here, we report that the splicing factor SWELLMAP 2 (SMP2) suppresses photomorphogenesis in the light. SMP2 physically interacts with phyB and colocalizes with phyB in photobodies after light exposure. Genetic analyses show that SMP2 antagonizes phyB signaling to promote hypocotyl elongation in the light. The homologs of SMP2 in yeast and human belong to second-step splicing factors required for proper selection of the 3' splice site (3'SS) of an intron. Notably, SMP2 reduces the abundance of the functional REVEILLE 8 a (RVE8a) form, probably by determining the 3'SS, and thereby inhibits RVE8-mediated transcriptional activation of clock genes containing evening elements (EE). Finally, SMP2-mediated reduction of functional RVE8 isoform promotes phytochrome interacting factor 4 (PIF4) expression to fine-tune hypocotyl elongation in the light. Taken together, our data unveil a phyB-interacting splicing factor that negatively regulates photomorphogenesis, providing additional information for further mechanistic investigations regarding phyB-controlled AS of light- and clock-related genes.

8.
Front Public Health ; 9: 794195, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34869197

RESUMO

In the post-epidemic era, green finance plays a more significant role in supporting the "green recovery" of the economy, so it is necessary to evaluate the implementation effect of previous green financial policies. In 2017, the green finance reform and innovation pilot zone set up in five provinces and autonomous regions made an exploration in the development of green finance. From the perspective of micro-enterprises, can this policy play a beneficial policy effect in the long run? Based on the quasi-natural experiment of green finance pilot, using the data of A-share listed companies, this paper empirically tests the impact of pilot policies on the long-term value of green enterprises in pilot areas. It is found that, compared with non-pilot zones, the green finance pilot enables a significant increase in the Tobin Q-measured value of green enterprises in the pilot zones. Heterogeneity analysis shows that green finance pilot has a more significant impact on non-state-owned enterprises, enterprises in traditional industries, large enterprises, and enterprises in the eastern region of China. Green finance pilot zone can achieve better policy effects in areas with stronger environmental impact regulation and higher financial development levels. The mechanism test shows that the green finance pilot affects the long-term value of green enterprises through the capital market effect improving the stock trading activity of enterprises and through the real effect improving the operational efficiency and profitability of enterprises. From the perspective of micro-enterprises, this paper enriches the research on the development effect of green finance and provides theoretical support for the effect evaluation of green finance pilot policies.


Assuntos
Meio Ambiente , Indústrias , China , Eficiência
9.
BMC Urol ; 21(1): 149, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34736451

RESUMO

BACKGROUND: To explore whether opening the external urethral orifice in the coronal sulcus can reduce the incidence of epididymitis after operating on hypospadias with prostatic utricle cyst (PUC) connecting to the vas deferens. Group A consisted of 3 patients with severe hypospadias and PUC undergoing cystostomy, hypospadias correction and urethroplasty, along with the relocation of the external orifice of the urethra to the coronal sulcus. Group B consisted of 4 patients having initial hypospadias repaired with meatus in the orthotopic position in the glans, presenting with multiple epididymitis after hypospadias surgery and unsuccessful conservative treatment. MR confirmed that all the Group B patients had PUC connecting to the vas deferens. Group B patients underwent urethral dilatation along with urethral catheterization, cutting of the original corpus cavernosum that encapsulated the urethra, and extension of the position of the external urethral orifice to the coronal sulcus. RESULTS: In group A, 3 children underwent bladder fistula removal 2 weeks after the operation. The penis developed normally without any complications. Four children in group B underwent stent removal 12 weeks after operation, and one patient was still stenosed and dilated again. All patients in group B were followed without epididymitis recurrence. CONCLUSIONS: For patients with hypospadias complicating with a PUC, connecting to one side of the vas deferens, the positioning of the external urethral orifice in the coronary sulcus would be helpful to reduce the occurrence of epididymitis.


Assuntos
Cistos/cirurgia , Hipospadia/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Doenças Prostáticas/cirurgia , Procedimentos Cirúrgicos Urológicos Masculinos/métodos , Cateterismo , Pré-Escolar , Cistostomia , Cistos/complicações , Cistos/diagnóstico por imagem , Dilatação , Epididimite/etiologia , Epididimite/prevenção & controle , Humanos , Hipospadia/complicações , Hipospadia/diagnóstico por imagem , Masculino , Complicações Pós-Operatórias , Doenças Prostáticas/complicações , Doenças Prostáticas/diagnóstico por imagem , Procedimentos de Cirurgia Plástica/efeitos adversos , Stents , Procedimentos Cirúrgicos Urológicos Masculinos/efeitos adversos
10.
Materials (Basel) ; 14(16)2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34443220

RESUMO

By optimizing the distribution of steel fibers in fiber-reinforced cementitious mortar (FRCM) through the layered structure, the role of fibers can be fully utilized, thus improving the flexural behavior. In this study, the flexural behavior of layered FRCM at different thicknesses (25 mm, 50 mm, 75 mm, 100 mm) of the steel fiber layer was investigated. The evolution of the crack propagation behavior was analyzed using the digital image correlation (DIC) technique. The results showed that the steel fiber layer thickness of 75 mm has the best flexural behavior. Moreover, the crack propagation path is more tortuous. The maximum value of crack opening displacement (COM) increases with the increase in fiber thickness. In addition, increasing the bottom layer thickness can increase the height of the tensile zone, but the interface inhibits the increase of the tensile zone.

11.
Environ Toxicol Pharmacol ; 86: 103669, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33964399

RESUMO

The wide applications of titanium dioxide nanoparticles (TNP) and ubiquitous cadmium (Cd) pollution increase the chances of their co-existence in the environment and also pose potential health risks to humans. However, toxicological understanding of effects of co-exposures of TNP and Cd to mammals is still lacking. In this study, non-lethal doses of TNP and CdCl2 were intravenously co-administered to healthy or Concanavalin A (ConA)-induced acute hepatitis mice. Co-exposures of TNP and CdCl2 increased the accumulation of Cd2+ in the liver of hepatitis mice, which was 1.42-fold higher than that of healthy mice. Co-exposures also caused liver damage only in hepatitis mice on the basis of histopathological and biochemical evidence. Further study showed that co-exposure upregulated hepatic oxidative stress, which further induced autophagy and apoptosis only in the liver of hepatitis mice. This finding underlines the potential toxicological consequences of co-exposures of TNP and CdCl2 in hepatitis sufferers.


Assuntos
Cádmio/toxicidade , Doença Hepática Induzida por Substâncias e Drogas , Hepatite , Nanopartículas/toxicidade , Titânio/toxicidade , Doença Aguda , Animais , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Concanavalina A , Interações Medicamentosas , Feminino , Hepatite/metabolismo , Hepatite/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Camundongos Endogâmicos BALB C , Estresse Oxidativo/efeitos dos fármacos
12.
World J Clin Cases ; 7(22): 3807-3811, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31799308

RESUMO

BACKGROUND: Congenital scrotal agenesis (CSA) is very rare. There are 11 cases of congenital scrotal agenesis or absence reported in the literature, most of which are bilateral and accompanied by cryptorchidism. Only two cases of which are unilateral scrotal agenesis and not accompanied by cryptorchidism. This is the first reported case of unilateral scrotal agenesis with cryptorchidism and scrotoplasty. CASE SUMMARY: A 2-year-old boy was admitted to our hospital with left cryptorchidism and ipsilateral CSA. An innovative method was used in the patient where a scrotal skin pedicle from the right part of scrotal skin was transplanted to the left side. At the same time, descent orchiopexy was performed. At the 4-mo follow-up, the left testicle was located in the scrotum and the size and shape were normal. CONCLUSION: For unilateral CSA with ipsilateral cryptorchidism, contralateral scrotal pedicle transplantation and descent orchiopexy appear to be a successful surgical option.

13.
Bioengineered ; 10(1): 13-22, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30836830

RESUMO

The deep-sea bacterium strain FA13 was isolated from the sediment of the South Atlantic Ocean and identified as Bacillus circulans based on 16S ribosomal DNA sequence. Through liquid fermentation with five media, the cell-free supernatant fermented with ISP2 showed the highest inhibition activities against mycelial growth of Aspergillus parasiticus mutant strain NFRI-95 and accumulation of norsolorinic acid, a precursor for aflatoxin production. Based on ISP2, uniform design was used to optimize medium formula and fermentation conditions. After optimization, the inhibition efficacy of the 20-time diluted supernatant against A. parasiticus NFRI-95 mycelial growth and aflatoxin production was increased from 0-23.1% to 100%. Moreover, compared to the original protocol, medium cost and fermentation temperature were significantly reduced, and dependence on seawater was completely relieved, thus preventing the fermentor from corrosion. This is the first report of a deep-sea microorganism which can inhibit A. parasiticus NFRI-95 mycelial growth and aflatoxin production.


Assuntos
Aflatoxinas/antagonistas & inibidores , Antraquinonas/antagonistas & inibidores , Antitoxinas/isolamento & purificação , Aspergillus/efeitos dos fármacos , Bacillus/metabolismo , Micélio/efeitos dos fármacos , Aflatoxinas/biossíntese , Antraquinonas/metabolismo , Antitoxinas/farmacologia , Organismos Aquáticos , Aspergillus/crescimento & desenvolvimento , Aspergillus/metabolismo , Aspergillus/patogenicidade , Oceano Atlântico , Bacillus/classificação , Bacillus/genética , Bacillus/isolamento & purificação , Reatores Biológicos , Meios de Cultura/química , Análise Fatorial , Fermentação , Sedimentos Geológicos/microbiologia , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Micélio/patogenicidade , Filogenia , RNA Ribossômico 16S/genética , Temperatura
14.
Medicine (Baltimore) ; 96(4): e5846, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28121930

RESUMO

BACKGROUND: Brachial plexus block (BPB) for upper extremity surgery provides superior analgesia, but this advantage is limited by the pharmacological duration of local anesthetics. Dexmedetomidine (DEX) as a local anesthetics adjuvant for BPB has been utilized to prolong the duration of the nerve block in some randomized controlled trials (RCTs) but is far from unanimous in the efficacy and safety of the perineural route. Hence, an updated meta-analysis was conducted to assess the efficacy and safety of DEX as local anesthetic adjuvants on BPB. METHODS: A search in electronic databases was conducted to collect the RCTs that investigated the impact of adding DEX to local anesthetics for BPB. Sensory block duration, motor block duration, onset time of sensory and motor block, time to first analgesic request, the common adverse effects were analyzed. RESULTS: Eighteen trails (1014 patients) were included with 515 patients receiving perineural DEX. The addition of DEX prolonged the duration of sensory block (WMD 257 minutes, 95%CI 191.79-322.24, P < 0.001), motor block (WMD 242 minutes, 95%CI 174.94-309.34, P < 0.001), and analgesia (WMD 26 6 minutes, 95%CI 190.75-342.81, P < 0.001). Perineural DEX also increased the risk of bradycardia (OR=8.25, 95%CI 3.95-17.24, P < 0.001), hypotension (OR = 5.62, 95%CI 1.52-20.79, P < 0.01), and somnolence (OR = 19.67, 95%CI 3.94-98.09, P < 0.001). There was a lack of evidence that perineural DEX increased the risk of other adverse events. CONCLUSIONS: DEX is a potential anesthetic adjuvant that can facilitate better anesthesia and analgesia when administered in BPB. However, it also increased the risk of bradycardia, hypotension, and somnolence. Further research should focus on the efficacy and safety of the preneural administration of DEX.


Assuntos
Adjuvantes Anestésicos/administração & dosagem , Analgésicos não Narcóticos/administração & dosagem , Anestésicos Locais/administração & dosagem , Bloqueio do Plexo Braquial/métodos , Dexmedetomidina/administração & dosagem , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Extremidade Superior/cirurgia
15.
Neurosci Lett ; 615: 83-7, 2016 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-26808643

RESUMO

It is well established that HIV-1-infected mononuclear phagocytes release platelet activating factor (PAF) and elevated levels of PAF have been detected in blood and in the cerebrospinal fluid (CSF) of acquired immunodeficiency syndrome (AIDS) patients with HIV-associated neurocognitive disorders (HAND). It is our hypothesis that the elevated levels of PAF alter long-term potentiation (LTP) in the hippocampus, leading to neurocognitive dysfunction. To test this hypothesis, we studied the effects of PAF on LTP in the CA1 region of rat hippocampal slices. Our results showed incubation of hippocampal slices with PAF attenuated LTP. The PAF-mediated attenuation was blocked by ginkgolide B, a PAF receptor antagonist, suggesting PAF attenuation of LTP via PAF receptors. Application of lyso-PAF, an inactive PAF analog, had no apparent effect on LTP. Further investigation revealed an involvement of tyrosine kinase in PAF attenuation of LTP, which was demonstrated by lavendustin A (a specific protein tyrosine kinase inhibitor) blockage of PAF attenuation of LTP. As LTP is widely considered as the cellular and synaptic basis for learning and memory, the attenuation of LTP by PAF may contribute at least in part to the HAND pathogenesis.


Assuntos
Hipocampo/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , Fator de Ativação de Plaquetas/farmacologia , Proteínas Tirosina Quinases/metabolismo , Animais , Potenciais Pós-Sinápticos Excitadores , Hipocampo/fisiologia , Técnicas In Vitro , Masculino , Fator de Ativação de Plaquetas/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais
16.
Meat Sci ; 106: 61-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25885797

RESUMO

Herein, we developed a novel integrated device to perform phase separation based on ultrasound-assisted, salt-induced, liquid-liquid microextraction for determination of five fluoroquinones in meats by HPLC analysis. The novel integrated device consisted of three simple HDPE (high density polyethylene) parts that were used to separate the solvent from the aqueous solution prior to retrieving the extractant. The extraction parameters were optimized using the response surface method based on central composite design: 589µL of acetone solvent, pH2.1, 4.1min extraction time and 3.5g of Na2SO4. The limits of detection were 0.056-0.64 µgkg(-1) and recoveries were 87.2-110.6% for the five fluoroquinones in muscle tissue from fish, chicken, pork and beef. This method is easily constructed from inexpensive materials, extraction efficiency is high, and the approach is compatible with HPLC analysis. Thus, it has excellent prospects for sample pre-treatment and analysis of fluoroquinones in meat samples.


Assuntos
Antibacterianos/análise , Resíduos de Drogas/análise , Fluoroquinolonas/análise , Contaminação de Alimentos , Inspeção de Alimentos/métodos , Carne/análise , Alimentos Marinhos/análise , Acetona/química , Animais , Antibacterianos/química , Bovinos , Galinhas , China , Resíduos de Drogas/química , Estudos de Viabilidade , Peixes , Fluoroquinolonas/química , Inspeção de Alimentos/instrumentação , Indicadores e Reagentes/química , Limite de Detecção , Microextração em Fase Líquida/instrumentação , Solubilidade , Solventes/química , Sulfitos/química , Sus scrofa , Ultrassom
17.
Antioxid Redox Signal ; 23(2): 129-47, 2015 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-25756524

RESUMO

AIMS: The mechanisms underlying numerous biological roles of hydrogen sulfide (H2S) remain largely unknown. We have previously reported an inhibitory role of H2S in the L-type calcium channels in cardiomyocytes. This prompts us to examine the mechanisms underlying the potential regulation of H2S on the ion channels. RESULTS: H2S showed a novel inhibitory effect on Ito potassium channels, and this effect was blocked by mutation at the Cys320 and/or Cys529 residues of the Kv4.2 subunit. H2S broke the disulfide bridge between a pair of oxidized cysteine residues; however, it did not modify single cysteine residues. H2S extended action potential duration in epicardial myocytes and regularized fatal arrhythmia in a rat model of myocardial infarction. H2S treatment significantly increased survival by ∼1.4-fold in the critical 2-h time window after myocardial infarction with a protection against ventricular premature beats and fatal arrhythmia. However, H2S did not change the function of other ion channels, including IK1 and INa. INNOVATION AND CONCLUSION: H2S targets the Cys320/Cys529 motif in Kv4.2 to regulate the Ito potassium channels. H2S also shows a potent regularizing effect against fatal arrhythmia in a rat model of myocardial infarction. The study provides the first piece of evidence for the role of H2S in regulating Ito potassium channels and also the specific motif in an ion channel labile for H2S regulation.


Assuntos
Motivos de Aminoácidos/efeitos dos fármacos , Arritmias Cardíacas/metabolismo , Cisteína/metabolismo , Sulfeto de Hidrogênio/farmacologia , Infarto do Miocárdio/metabolismo , Canais de Potássio Shal/metabolismo , Animais , Arritmias Cardíacas/tratamento farmacológico , Dissulfetos/metabolismo , Células HEK293 , Humanos , Sulfeto de Hidrogênio/uso terapêutico , Masculino , Mutação , Infarto do Miocárdio/tratamento farmacológico , Miócitos Cardíacos/metabolismo , Ratos , Canais de Potássio Shal/antagonistas & inibidores , Canais de Potássio Shal/genética
18.
Artigo em Inglês | MEDLINE | ID: mdl-25660716

RESUMO

Herein, we developed a novel integrated device to perform phase separation based on ultrasound-assisted salt-induced liquid-liquid microextraction for determination of five fluoroquinones (FQs) in human body fluids. The integrated device consisted of three simple HDPE components used to separate the extraction solvent from the aqueous phase prior to retrieving the extractant. A series of extraction parameters were optimized using the response surface method based on central composite design. Optimal conditions consisted of 945µL acetone extraction solvent, pH 2.1, 4.1min stir time, 5.9g Na2SO4, and 4.0min centrifugation. Under optimized conditions, the limits of detection (at S/N=3) were 0.12-0.66µgL(-1), the linear range was 0.5-500µgL(-1) and recoveries were 92.6-110.9% for the five FQs extracted from plasma and urine. The proposed method has several advantages, such as easy construction from inexpensive materials, high extraction efficiency, short extraction time, and compatibility with HPLC analysis. Thus, this method shows excellent prospects for sample pretreatment and analysis of FQs in human body fluids.


Assuntos
Cromatografia Líquida/métodos , Fluoroquinolonas , Microextração em Fase Líquida/métodos , Feminino , Fluoroquinolonas/sangue , Fluoroquinolonas/química , Fluoroquinolonas/isolamento & purificação , Fluoroquinolonas/urina , Humanos , Limite de Detecção , Masculino , Reprodutibilidade dos Testes , Sonicação , Temperatura
19.
Ultrasound Q ; 31(1): 59-62, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25706366

RESUMO

The effect of scanning angle and region of interest (ROI) depth on shear-wave velocity (SWV) was investigated in this study. Shear-wave velocity of ox liver ex vivo was measured with different approaches. Region of interest was set underneath the liver capsule at depths of 1, 2, 3, 4, and 5 cm. Three groups of measurements were performed at different scanning angles. One group of measurement was conducted with a scanning angle of 0 to 15 degrees from the midline, and the other 2 groups were performed with scanning angles of 15 to 30 degrees and 30 to 45 degrees. The data on SWV from different scan angles and ROI depths were analyzed statistically. Scanning angle and ROI depth were found to be the 2 factors that affect SWV. Interaction was observed between the scan angle and ROI depth. The data at different depths within 0- to 15-degree scanning angles exhibited no significant difference. However, the reliability of SWV decreased with the increase in ROI depth. In the groups of 15 to 30 degrees and 30 to 45 degrees, a significant difference was found between the 2 different measured depths. Scanning angle and ROI depth affected the reliability of SWV measurement. The scanning angle should be confined within 15 degrees from the midline. Therefore, SWV from shallow ROI is more reliable than that at deep ROI.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Aumento da Imagem/métodos , Fígado/diagnóstico por imagem , Fígado/fisiologia , Posicionamento do Paciente/métodos , Animais , Bovinos , Módulo de Elasticidade/fisiologia , Técnicas In Vitro , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resistência ao Cisalhamento/fisiologia , Estresse Mecânico , Tato , Interface Usuário-Computador
20.
Food Chem ; 173: 1213-9, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25466146

RESUMO

In solidified floating organic droplet microextraction, the solidified organic phase formed a concave meniscus on the water surface, and the solidified layer was easily broken into pieces when using a medical spoon to collect it, resulting in a slow and difficult whole collection. A novel method, nitrogen-blowing salt-induced solidified floating organic droplet microextraction, was developed for pretreatment of the milk samples. After the procedures, the down layer salt and aqueous phase was discarded by opening the bottom cap. The remaining solidified solvent was easily and wholly collected by a medical spoon, resulting in a high extraction efficiency. The similarly high deprotein rate (91-96%) was obtained between using acetonitrile and without using organic solvent as precipitating agent. Under optimized conditions, the limits of detection were 0.34-0.87 µg/L, the linear range was 1-500 µg/L, the extraction recoveries were 79.2-105.2%, and the enrichment factors were 105.8-169.3 for five phenolic oestrogens.


Assuntos
Estrogênios/química , Leite/química , Nitrogênio/química , Fenóis/química , Sais/química , Animais , Cromatografia Líquida de Alta Pressão , Análise de Alimentos , Concentração de Íons de Hidrogênio , Limite de Detecção , Cloreto de Sódio/química , Solventes/química , Água/química
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